Ahmad Elgazzar, Haotian Wang and Shaoyun Hao were members of a Rice University team that recently published findings on how acid bubbling can improve CO2 reduction systems. Photo courtesy Rice.

In a new study published in the journal Science, a team of Rice University researchers shared findings on how acid bubbles can improve the stability of electrochemical devices that convert carbon dioxide into useful fuels and chemicals.

The team led by Rice associate professor Hoatian Wang addressed an issue in the performance and stability of CO2 reduction systems. The gas flow channels in the systems often clog due to salt buildup, reducing efficiency and causing the devices to fail prematurely after about 80 hours of operation.

“Salt precipitation blocks CO2 transport and floods the gas diffusion electrode, which leads to performance failure,” Wang said in a news release. “This typically happens within a few hundred hours, which is far from commercial viability.”

By using an acid-humidified CO2 technique, the team was able to extend the operational life of a CO2 reduction system more than 50-fold, demonstrating more than 4,500 hours of stable operation in a scaled-up reactor.

The Rice team made a simple swap with a significant impact. Instead of using water to humidify the CO2 gas input into the reactor, the team bubbled the gas through an acid solution such as hydrochloric, formic or acetic acid. This process made more soluble salt formations that did not crystallize or block the channels.

The process has major implications for an emerging green technology known as electrochemical CO2 reduction, or CO2RR, that transforms climate-warming CO2 into products like carbon monoxide, ethylene, or alcohols. The products can be further refined into fuels or feedstocks.

“Using the traditional method of water-humidified CO2 could lead to salt formation in the cathode gas flow channels,” Shaoyun Hao, postdoctoral research associate in chemical and biomolecular engineering at Rice and co-first author, explained in the news release. “We hypothesized — and confirmed — that acid vapor could dissolve the salt and convert the low solubility KHCO3 into salt with higher solubility, thus shifting the solubility balance just enough to avoid clogging without affecting catalyst performance.”

The Rice team believes the work can lead to more scalable CO2 electrolyzers, which is vital if the technology is to be deployed at industrial scales as part of carbon capture and utilization strategies. Since the approach itself is relatively simple, it could lead to a more cost-effective and efficient solution. It also worked well with multiple catalyst types, including zinc oxide, copper oxide and bismuth oxide, which are allo used to target different CO2RR products.

“Our method addresses a long-standing obstacle with a low-cost, easily implementable solution,” Ahmad Elgazzar, co-first author and graduate student in chemical and biomolecular engineering at Rice, added in the release. “It’s a step toward making carbon utilization technologies more commercially viable and more sustainable.”

A team led by Wang and in collaboration with researchers from the University of Houston also shared findings on salt precipitation buildup and CO2RR in a recent edition of the journal Nature Energy. Read more here.

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NRG makes latest partnership to grow virtual power plant

VPP partners

Houston-based NRG Energy recently announced a new long-term partnership with San Francisco-based Sunrun that aims to meet Texas’ surging energy demands and accelerate the adoption of home battery storage in Texas. The partnership also aligns with NRG’s goal of developing a 1-gigawatt virtual power plant by connecting thousands of decentralized energy sources by 2035.

Through the partnership, the companies will offer Texas residents home energy solutions that pair Sunrun’s solar-plus-storage systems with optimized rate plans and smart battery programming through Reliant, NRG’s retail electricity provider. As new customers enroll, their stored energy can be aggregated and dispatched to the ERCOT grid, according to a news release.

Additionally, Sunrun and NRG will work to create customer plans that aggregate and dispatch distributed power and provide electricity to Texas’ grid during peak periods.

“Texas is growing fast, and our electricity supply must keep pace,” Brad Bentley, executive vice president and president of NRG Consumer, said in the release. “By teaming up with Sunrun, we’re unlocking a new source of dispatchable, flexible energy while giving customers the opportunity to unlock value from their homes and contribute to a more resilient grid

Participating Reliant customers will be paid for sharing their stored solar energy through the partnership. Sunrun will be compensated for aggregating the stored capacity.

“This partnership demonstrates the scale and strength of Sunrun’s storage and solar distributed power plant assets,” Sunrun CEO Mary Powell added in the release. “We are delivering critical energy infrastructure that gives Texas families affordable, resilient power and builds a reliable, flexible power plant for the grid.”

In December, Reliant also teamed up with San Francisco tech company GoodLeap to bolster residential battery participation and accelerate the growth of NRG’s virtual power plant network in Texas.

In 2024, NRG partnered with California-based Renew Home to distribute hundreds of thousands of VPP-enabled smart thermostats by 2035 to help households manage and lower their energy costs. At the time, the company reported that its 1-gigawatt VPP would be able to provide energy to 200,000 homes during peak demand.

10+ exciting energy breakthroughs made by Houston teams in 2025

Year In Review

Editor's note: As 2025 comes to a close, we're revisiting the biggest headlines and major milestones of the energy sector this year. Here are the most exciting scientific breakthroughs made by Houstonians this year that are poised to shape the future of energy:

Rice University team develops eco-friendly method to destroy 'forever chemicals' in water

Rice University researchers have developed a new method for removing PFAS from water that works 100 times faster than traditional filters. Photo via Rice University.

Rice University researchers have teamed up with South Korean scientists to develop the first eco-friendly technology that captures and destroys toxic “forever chemicals,” or PFAS, in water. The Rice-led study centered on a layered double hydroxide (LDH) material made from copper and aluminum that could rapidly capture PFAS and be used to destroy the chemicals.

UH researchers make breakthrough in cutting carbon capture costs

UH carbon capture cost cutting

A team from UH has published two breakthrough studies that could help cut costs and boost efficiency in carbon capture. Photo courtesy UH.

A team of researchers at the University of Houston has made two breakthroughs in addressing climate change and potentially reducing the cost of capturing harmful emissions from power plants. Led by Professor Mim Rahimi at UH’s Cullen College of Engineering, the team first introduced a membraneless electrochemical process that cuts energy requirements and costs for amine-based carbon dioxide capture during the acid gas sweetening process.The second breakthrough displayed a reversible flow battery architecture that absorbs CO2 during charging and releases it upon discharge.

Houston team’s discovery brings solid-state batteries closer to EV use

Houston researchers have uncovered why solid-state batteries break down and what could be done to slow the process. Photo via Getty Images.

A team of researchers from the University of Houston, Rice University and Brown University has uncovered new findings that could extend battery life and potentially change the electric vehicle landscape. Their work deployed a powerful, high-resolution imaging technique known as operando scanning electron microscopy to better understand why solid-state batteries break down and what could be done to slow the process.

Houston researchers make breakthrough on electricity-generating bacteria

A team of Rice researchers, including Caroline Ajo-Franklin and Biki Bapi Kundu, has uncovered how certain bacteria breathe by generating electricity. Photo by Jeff Fitlow/Rice University.

Research from Rice University that merges biology with electrochemistry has uncovered new findings on how some bacteria generate electricity. Research showed how some bacteria use compounds called naphthoquinones, rather than oxygen, to transfer electrons to external surfaces in a process known as extracellular respiration. In other words, the bacteria are exhale electricity as they breathe. This process has been observed by scientists for years, but the Rice team's deeper understanding of its mechanism is a major breakthrough, with implications for the clean energy and industrial biotechnology sectors, according to the university.

Rice researchers' quantum breakthrough could pave the way for next-gen superconductors

Researchers from Rice University say their recent findings could revolutionize power grids, making energy transmission more efficient. Image via Getty Images.

A study from researchers at Rice University could lead to future advances in superconductors with the potential to transform energy use. The study revealed that electrons in strange metals, which exhibit unusual resistance to electricity and behave strangely at low temperatures, become more entangled at a specific tipping point, shedding new light on these materials. The materials share a close connection with high-temperature superconductors, which have the potential to transmit electricity without energy loss, according to the researchers. By unblocking their properties, researchers believe this could revolutionize power grids and make energy transmission more efficient.

UH researchers develop breakthrough material to boost efficiency of sodium-ion batteries

A team at the University of Houston is changing the game for sodium-ion batteries. Photo via Getty Images

A research lab at the University of Houston developed a new type of material for sodium-ion batteries that could make them more efficient and boost their energy performance. The Canepa Research Laboratory is working on a new material called sodium vanadium phosphate, which improves sodium-ion battery performance by increasing the energy density. This material brings sodium technology closer to competing with lithium-ion batteries, according to the researchers.

Houston researchers make headway on developing low-cost sodium-ion batteries

Houston researchers make headway on developing low-cost sodium-ion batteries

Rice's Atin Pramanik and a team in Pulickel Ajayan's lab shared new findings that offer a sustainable alternative to lithium batteries by enhancing sodium and potassium ion storage. Photo by Jeff Fitlow/Courtesy Rice University

A new study by researchers from Rice University’s Department of Materials Science and NanoEngineering, Baylor University and the Indian Institute of Science Education and Research Thiruvananthapuram has introduced a solution that could help develop more affordable and sustainable sodium-ion batteries. The team worked with tiny cone- and disc-shaped carbon materials from oil and gas industry byproducts with a pure graphitic structure. The forms allow for more efficient energy storage with larger sodium and potassium ions, which is a challenge for anodes in battery research. Sodium and potassium are more widely available and cheaper than lithium.

Houston scientists develop 'recharge-to-recycle' reactor for lithium-ion batteries

Rice University scientists' “recharge-to-recycle” reactor has major implications for the electric vehicle sector. Photo courtesy Jorge Vidal/Rice University.

Engineers at Rice University have developed a cleaner, innovative process to turn end-of-life lithium-ion battery waste into new lithium feedstock. The findings demonstrate how the team’s new “recharge-to-recycle” reactor recharges the battery’s waste cathode materials to coax out lithium ions into water. The team was then able to form high-purity lithium hydroxide, which was clean enough to feed directly back into battery manufacturing. The study has major implications for the electric vehicle sector, which significantly contributes to the waste stream from end-of-life battery packs.

Houston researchers develop strong biomaterial that could replace plastic

A team led by M.A.S.R. Saadi and Muhammad Maksud Rahman has developed a biomaterial that they hope could be used for the “next disposable water bottle." Photo courtesy Rice University.

Collaborators from two Houston universities are leading the way in engineering a biomaterial into a scalable, multifunctional material that could potentially replace plastic. The study introduced a biosynthesis technique that aligns bacterial cellulose fibers in real-time, which resulted in robust biopolymer sheets with “exceptional mechanical properties.” Ultimately, the scientists hope this discovery could be used for the “next disposable water bottle,” which would be made by biodegradable biopolymers in bacterial cellulose, an abundant resource on Earth. Additionally, the team sees applications for the materials in the packaging, breathable textiles, electronics, food and energy sectors.

Houston researchers reach 'surprising' revelation in materials recycling efforts

A team led by Matteo Pasquali, director of Rice’s Carbon Hub, has unveiled how carbon nanotube fibers can be a sustainable alternative to materials like steel, copper and aluminum. Photo by Jeff Fitlow/ Courtesy Rice University

Researchers at Rice University have demonstrated how carbon nanotube (CNT) fibers can be fully recycled without any loss in their structure or properties. The discovery shows that CNT fibers could be used as a sustainable alternative to traditional materials like metals, polymers and the larger, harder-to-recycle carbon fibers, which the team hopes can pave the way for more sustainable and efficient recycling efforts.